How are fossils formed? How fossils are formed

Here's how fossils are formed:

There are two types of fossils, one is formed by the decomposition of the organic part of the body and the petrification of the hard part after the death of the organism on the earth. The other is the traces left by those creatures, which are formed by turning into stone after petrification. It takes hundreds of millions of years to form and can be divided into plant fossils including roots and leaves, and animal fossils including teeth and footprints.

There are two kinds of fossils, one is that after the death of organisms on the earth, the body is buried by sediment, the organic part of the body is decomposed, and the hard part such as the shell, bones, branches and leaves are preserved, and petrified together with the surrounding sediment and turned into stone, thus forming.

The other is the traces left by those creatures, which are also formed by petrifying and turning into stone. In general, fossils take hundreds of millions of years to form. It retains the form and structure of those organisms that once lived on the earth, allowing modern people to understand the ecological environment hundreds of millions of years ago and the changes of organisms from ancient times to the present.

Fossils are divided into plant and animal species, and plant fossils include roots, wood, leaves, spores, seeds, fruits, divisions, phytolites, and amber in smaller quantities. Animal fossils include invertebrates and vertebrates, and the common fossils are teeth, bones, footprints, crawling marks, holes, etc., which are more numerous.

After the biological remains and their life activities are buried by sediments, they go through a long geological time, and with the diagenesis of sediments, the biological remains or relics buried in the sediments are transformed by physical and chemical processes (often accompanied by mineral metasomatism and filling) and finally form fossils.

Fossils are the remains of paleontology, relics, or remains that remain in rocks, most commonly bones and shells.

The word fossil is derived from the Latin fossillis, which means to dig. Fossils are the main research objects of paleontology, which provide evidence for the study of animal and plant life history in geological periods. There have long been records of fossils in ancient Chinese books, such as Ji Ran in the Spring and Autumn Period and Wu Jin in the Three Kingdoms Period, both of which have mentioned the "dragon bones" produced in Shanxi Province, and the "dragon bones" are fossils of bones and teeth of ancient vertebrates.

The so-called fossils refer to the paleontological relics and living relics of the geological history period preserved in the rock formations, as well as the residual organic molecules of biological origin.

In the long geological time, there have been countless creatures living on the earth, and many of the remains of these creatures after death or traces left over from life were buried by the sediment of the time.

In the years that followed, the organic matter in the remains of these organisms was decomposed, and the hard parts such as the shells, bones, branches and leaves, along with the surrounding sediment, were petrified and turned into stone, but their original form, structure (and even some subtle internal structures) remained.

In the same way, the traces left by those creatures when they lived can be preserved in this way. We call the remains and remains of these petrified organisms fossils, and fossils generally take at least hundreds of millions of years to form.

Often, soft parts such as muscles or epidermis have eroded before they can be preserved, leaving only the more resistant parts, such as bones or shells. They are then replaced by minerals seeping into the surrounding sediment. Many of the fossils are also covered with the weight of the rocks on which they are flattened.

1. Fossils are the remains or relics of creatures in the distant past.

2. The organic matter in the biological remains is decomposed.

3. The hard part is petrified and turned into stone along with the surrounding sediment, but the original morphological structure of the creature is still preserved.

4. Fossils are formed by petrification after the remains of organisms or other living activities in the historical period of the earth are buried by sediments, and in the process of sediment compaction and consolidation.

Fossils are the relics of ancient creatures buried in the strata. The most common fossils are formed from teeth and bones. After the death of ancient animals, the internal organs, muscles and other soft tissues of the corpse will quickly decay, and the teeth and bones can be preserved for a longer time because there is less organic matter and more inorganic matter.

If the body happens to be buried in sediment, cut off from the air, the process of decay slows down. There is slow-flowing groundwater in the sediment voids. On the one hand, the water dissolves the minerals in the rock and sediment, and on the other hand, the excess minerals in the water precipitate or become crystals, which gradually seep into the bones buried in the sediment and fill the space left by the decay of the organic matter of the teeth and bones.

If the conditions are right, the minerals that seep into the bones from the outside can effectively replace the original organic matter of the bones before they decay and disintegrate, and the teeth and bones are preserved as fossils. Because a large number of minerals in fossils are slowly replaced by extremely careful organic matter, the original shape of teeth and bones can be preserved intact, and even the shape of tissues that can be seen by electron microscopy can be preserved as they are. Over time, the weight of the bones increases, and the original teeth and bones become stones that still preserve the original shape and internal structure of the teeth and bones, a process called "petrification".

In addition to teeth and bones, the feces of some animals can also be fossilized. For example, some carnivores eat meat with broken bones, and there are many undigested broken bones in the feces, which are not easy to decay, so they can become fossils. Footprints can also become fossils.

People or animals step on the mud and sand, causing footprints. When the sediment dried, the footprints were filled with other substances. Both substances are preserved by the petrification of minerals that later seep in, but the properties of the two substances are different, the hardness is different, and the degree of weathering or destruction is also different.

When one substance is weathered or destroyed, the other appears as fossilized footprints.

1When the animal dies, the soft tissue is decomposed, and the hard tissues such as bones and teeth are preserved.

2 Over time, these hard tissues are surrounded by sedimentary layers and mineralized.

3 Thousands of years later, the fossils that have been formed rise close to the surface due to the action of the earth's crustal movements.

4. The erosion and collapse of the disguise are really exposed.

This is how the fossils were formed, and the fossils are only dinosaur fossils? After reading it, I understand!

In fact, for a long time, fossilization was considered to be a simple "petrification", and it was only later that humans gradually understood the principle of fossil formation. It is a very complex process, a combination of three phenomena: biological, physical, and chemical. And the formation of fossils requires some special conditions:

First, dead organisms are quickly buried in sand, silt, or river mud without decomposing.

The bottom of the sea and the bottom of the lake are very conducive environments, as are the grasslands and deserts. Second, the organism does not decay, but gradually replaces the organism's organic matter with minerals. Finally, for fossils to remain unchanged for millions of years, they must be petrified without undergoing any geological changes.

Collective living in clusters.

The first condition for the formation of fossils by death is the death of a large number of organisms, and the premise of the death of a large number of organisms is that a large number of organisms live together. In the case of polyps, they live in colonies and have roughly the same requirements for the environmental conditions in which they live, and if these basic living conditions are changed, there is a risk that the mass death of the polyps will occur. Therefore, for polyps, fossilization is more likely.

Quickly bury and store in time.

The second condition for the formation of fossils is that the organism must be buried quickly after death, otherwise its remains will be eaten by other animals, or oxidized and decayed. Even hard shells, bones, etc., will turn into powder and disappear when they are weathered and corroded over time.

Superiority of hardening.

The vast majority of fossils are hard parts of living organisms, such as bones, teeth, horns, tree trunks, spores, pollen, etc., some of which contain a considerable amount of inorganic substances, which are not only not easy to decay and decompose, but are easy to alternate with minerals from the outside world, thereby strengthening their structure. So, common fossils actually refer to fossils of the hard parts of living organisms.

Petrochemical reinforcement. The fourth condition for the formation of fossils is the "petrification" process, which basically has two categories: chemical processes and physical processes. The so-called chemical process refers to the fact that when a high-concentration aqueous mineral solution (mainly calcium carbonate solution, silica and pyrite solution) flows through the biological remains, the original components of the hard part of the biological remains are gradually replaced by the minerals in the groundwater solution, and over time they become almost new mineral components, while the morphological characteristics of the hard parts and even the subtle internal textures are completely preserved.

The most common are fossilized bones, shells, and plant stems. The so-called physical process refers to the imprint of the shape of an organism or the pattern of its shell on a rock formation, or the filling of voids such as the shell and bones of an organism with sediment or other minerals. For example, on a beach, river beach or lake beach, shelled animals fall on a soft layer of sediment, covered with new sediment, and the remains are tightly pressed, and over time, the beach will be imprinted with animal shell patterns, animal footprints, etc., and eventually become fossils.

After the death of animals and plants, their bodies are quickly covered with sediment and cut off from the air, and after hundreds of millions of years of changes, they become fossils!

It is formed by the gradual petrification of the earth's crust due to the high temperature and high pressure environment in the anoxic environment.

1. Fossils are the remains or ruins of organisms in the distant past, and 2. The organic matter in the remains of living beings is decomposed.

3. The hard part was petrified and turned into stone along with the sediment that surrounded it.

4 But the original morphological structure of the organism remains.

This is how the fossils were formed, and the fossils are only dinosaur fossils? After reading it, I understand!